1. Field of the Invention
The present invention relates to electrical power tools. More particularly, the present invention relates to electrical power tools that are constructed to trim or groove work-pieces such as woody materials.
2. Description of Related Art
An electrical power tool that is constructed to trim or groove a work-piece such as a woody material is generally known. Such an electrical power tool is called as a router or trimmer. The electrical power tool includes a tool main body having a spindle, and a base that is capable of supporting the tool main body and contacting the work-piece. In the electrical power tool, it is necessary to determine a position of a tool bit relative to the work-piece. Generally, in order to determine the position of the tool bit relative to the work-piece, a relative position of the tool main body to the base is determined, so that a relative position of the tool main body to the work-piece is determined. Thus, the position of the tool bit relative to the work-piece can be determined.
Such an electrical power tool is taught, for example, by U.S. Pat. No. 6,779,954 and Japanese Laid-Open Patent Publication Number 9-164503. The electrical power tool includes an elevating (raising and lowering) mechanism that is capable of adjusting the position of the tool bit relative to the work-piece. The elevating mechanism includes a threaded ring that is rotatably attached to the base. The threaded ring is threadably engaged with the tool main body. Therefore, when the threaded ring is rotated, the tool main body can be raised or lowered relative to the base, so that the relative position of the tool main body to the base can be changed or adjusted.
Such an electrical power tool is also taught, for example, by Japanese Laid-Open Patent Publication Number 2005-305683. The electrical power tool includes an elevating (raising and lowering) mechanism that is capable of adjusting the position of the tool bit relative to the work-piece. The elevating mechanism includes a threaded housing that is formed in the tool main body. The threaded housing is threadably engaged with the base. Therefore, when the threaded housing is rotated, the tool main body can be raised or lowered relative to the base, so that the relative position of the tool main body to the base can be adjusted. The elevating mechanism further includes a securing mechanism that is capable of selectively securing the threaded housing (the tool main body) to predetermined desired positions on the base. The securing mechanism has a lever that is capable of moving between a securing position and a releasing position, so that the threaded housing can be easily secured to and released from the base in one operation.
Generally, in some cases, the electrical power tool can be used while the tool main body is separated or detached from the base. That is, the tool main body can be used separately in some cases. In such a case, the tool main body must be removed from the base. However, in order to remove the tool main body from the base, a complicated and time-consuming work may be required. Thus, there is a need in the art for an improved electrical power tool.